Rail extrusion



FIG. 1 is a front end view thereof,

FIG. 2 is a left side view thereof,

FIG. 3 is a top side view thereof,

FIG. 4 is a right side view thereof,

FIG. 5 is a bottom side view thereof,

FIG. 6 is a back end view thereof; and,

FIG. 7 is a perspective view thereof. 

CLAIM The ornamental design for a rail extrusion, as shown. 